Group III-N semiconductor structures such as gallium nitride structures exhibit unique electronic properties including large bandgaps, which make them suitable for a wide range of applications from power electronics to light emitting diodes. The growth of these materials is generally performed on growth substrates with significant lattice mismatch such as silicon, silicon carbide (SiC) and sapphire. Amongst these substrates, the nitride materials grown on SiC provide the highest material quality. Nonetheless, the relatively high cost of SiC is a major obstacle in widespread use of this epitaxial scheme. Recently, there have been several reports on the growth of GaN on chemical vapor deposition (CVD) formed graphene, which was grown on copper substrates. Graphene has a honeycomb structure and therefore it can serve as a suitable epitaxial template for the growth of nitride materials. Nonetheless, the quality of the epitaxial GaN is limited by the highly granular graphene structure and also lack of nucleation sites due to the pristine crystalline structure of graphene.
The growth of high quality graphene with large grain boundaries has also been reported on SiC substrates. The presence of terraces on the SiC substrate will facilitate the nucleation of GaN layer on graphene. In addition, graphene is prevalently connected to the underlying SiC substrates through van der Waals bond/force, which is weak in nature. The layer transfer of nitride materials has been reported via different methods such as laser lift-off and the controlled spalling technique. The laser lift-off is primarily used for the transfer of nitride structures grown on silicon and sapphire, which calls for the removal of the growth substrate. Spalling-based methods, in general, are predicated on the propagation of a mode of fracture parallel to the surface that is induced by a tensile stressor layer.